Air Quality Management in Macao – assessment, development of an operational forecast, and future perspectives

A combination of assessment, operational forecast, and future perspective was thoroughly explored to provide an overview of the existing air quality problems in Macao. The levels of air pollution in Macao often exceed those recommended by the World Health Organization (WHO). In order for the population to take precautionary measures and avoid further health risks during high pollution episodes, it is important to develop a reliable air quality forecast. Statistical models based on linear multiple regression (MLR) and classification and regression trees (CART) analysis were successfully developed for Macao, to predict the next day concentrations of NO2, PM10, PM2.5, and O3. Meteorological variables were selected from an extensive list of possible variables, including geopotential height, relative humidity, atmospheric stability, and air temperature at different vertical levels. Air quality variables translate the resilience of the recent past concentrations of each pollutant and usually are maximum and/or the average of latest 24-hour levels. The models were applied in forecasting the next day average daily concentrations for NO2 and PM and maximum hourly O3 levels for five air quality monitoring stations. The results are expected to support an operational air quality forecast for Macao. The work involved two phases. On a first phase, the models utilized meteorological and air quality variables based on five years of historical data, from 2013 to 2017. Data from 2013 to 2016 were used to develop the statistical models and data from 2017 was used for validation purposes. All the developed models were statistically significantly valid with a 95% confidence level with high coefficients of determination (from 0.78 to 0.93) for all pollutants. On a second phase, these models were used with 2019 validation data, while a new set of models based on a more extended historical data series, from 2013 to 2018, were also validated with 2019 data. There were no significant differences in the coefficients of determination (R2 ) and minor improvements in root mean square errors (RMSE), mean absolute errors (MAE) and biases (BIAS) between the 2013 to 2016 and the 2013 to 2018 data models. In addition, for one air quality monitoring station (Taipa Ambient), the 2013 to 2018 model was applied for two days ahead (D2) forecast and the coefficient of determination (R2 ) was considerably less accurate to the one day ahead (D1) forecast, but still able to provide a reliable air quality forecast for Macao. To understand if the prediction model was robust to extreme variations in pollutants concentration, a test was performed under the circumstances of a high pollution episode for PM2.5 and O3 during 2019, and a low pollution episode during 2020. Regarding the high pollution episode, the period of the Chinese National Holiday of 2019 was selected, in which high concentration levels were identified for PM2.5 and O3, with peaks of daily concentration for PM2.5 levels exceeding 55 μg/m3 and the maximum hourly concentration for O3 levels exceeding 400 μg/m3 . For the low pollution episode, the 2020 period of implementation of the preventive measures for COVID-19 pandemic was selected, with a low record of daily concentration for PM2.5 levels at 2 μg/m3 and maximum hourly concentration for O3 levels at 50 μg/m3 . The 2013 to 2018 model successfully predicted the high pollution episode with high coefficients of determination (0.92 for PM2.5 and 0.82 for O3). Likewise, the low pollution episode was also correctly predicted with high coefficients of determination (0.86 and 0.84 for PM2.5 and O3, respectively). Overall, the results demonstrate that the statistical forecast model is robust and able to correctly reproduce extreme air pollution events of both high and low concentration levels. Machine learning methods maybe adopted to provide significant improvements in combination of multiple linear regression (MLR) and classification and regression tree (CART) to further improve the accuracy of the statistical forecast. The developed air pollution forecasting model may be combined with other measures to mitigate the impact of air pollution in Macao. These may include the establishment of low emission zones (LEZ), as enforced in some European cities, license plate restrictions and lottery policy, as used in some Asian, tax exemptions on electric vehicles (EVs) and exclusive corridors for public transportations

DARK-EARTH MANUAL: APPROACHING AN INK-BASED ART PRACTICE

This document examines a number of conceptual approaches to an ink-based art practice associated with the tradition of Chinese shuimo. The paper seeks meaningful ways to engage an art practice focused on ink’s tactility and materiality. It begins by mapping out a direction to develop a conceptually sound basis for such a practice. This is followed by an exploration of ink’s manufacturing history in the Chinese context. The methods of ink’s production reveal a materially destructive aspect that ultimately leads to a process of transformation. The burning of natural resources to make ink prompts an investigation into ink’s material, Shingly” character. A section of Martin Heidegger’s The Origin of the Work of Art is discussed in the third chapter in relation to my seeking of a renewed approach to ink practice. Concrete, ink-related examples are provided in the fourth and fifth chapters to demonstrate the applicability of the concepts explore

Liberalization of China-US air transport market: assessing the impacts of the 2004 and 2007 protocols

This paper examines China's considerations in reaching the 2004 and 2007 Air Service Agreement Protocols with the United States (US) and the impacts of such policy on the China–US market from the perspective of China. Analysis shows that the 2004 and 2007 protocols have profound impacts on the China–US market. The two protocols have been associated with phenomenal traffic growth and intensified competition. Passengers also benefit from much more choice in terms of both airlines and routing. Over time, Chinese carriers' operating performance and financial performance have gradually improved after the liberalization expressed in the protocols. However, the industry's hub-building initiatives are still seriously challenged by competing hubs in Seoul and Tokyo which have diverted substantial number of passengers moving between the China and US markets. Such issues have to be addressed in order to create a win–win outcome for both countries

2011 German Escherichia coli outbreak: Alignment-free whole-genome phylogeny by feature frequency profiles

Accuracy of SNP-based whole-genome phylogeny reconstruction relies heavily on quality of sequence alignment which is particularly hindered by poorly assembled genomes. Alignment-free methods might provide additional insights. Here, we constructed a whole-genome phylogeny of 9 E.coli isolates from the 2011 German outbreak against existing E. coli genomes using the alignment-free feature frequency profile method. In addition, we looked for gene elements that distinguish the outbreak group from the other E. coli strains and possibly accounted for the emergence of the outbreak isolates using the distinguishing feature analysis

Utility-Oriented Placement of Actuator Nodes with a Collaborative Serving Scheme for Facilitated Business and Working Environments

Places to be served by cyber-physical systems (CPS) are usually distributed unevenly over the area. Thus, different areas usually have different importance and values of serving. In other words, serving power can be excessive or insufficient in practice. Therefore, actuator nodes (ANs) in CPS should be focused on serving around points of interest (POIs) with considerations of “service utility.” In this paper, a utility-oriented AN placement framework with a collaborative serving scheme is proposed. Through spreading serving duties among correctly located ANs, deployment cost can be reduced, utility of ANs can be fully utilized, and the system longevity can be improved. The problem has been converted into a binary integer linear programming optimization problem. Service fading, 3D placements, multiscenario placements, and fault-tolerant placements have been modeled in the framework. An imitated example of a CPS deployment in a smart laboratory has been used for evaluations.published_or_final_versio

Advancements in using a machine design project for teaching introductory electrical engineering

Project-based learning is commonly used in teaching electrical/electronic engineering content. This paper analyses a proposed course that used a Rube Goldberg machine design project for introductory electrical engineering teaching. To facilitate students' learning, two main enhancements of the original course development are described: i) a refurnished project vehicle and new curriculum-framing questions have been proposed to assist students achieving the course's learning outcomes, and ii) tools for idea cultivation, design progress monitoring and design/learning collaboration technologies have been proposed to assist students to direct their learning. © 2013 IEEE.published_or_final_versio